1. Field of the Invention
The present invention relates to the automated production of quality optical assemblies. More particularly, the present invention relates to high-performance waveguides having a machine-readable identifier and automated production systems using the same.
2. Description of the Related Art
In recent years, optical assemblies have been recognized as offering a high potential for solving problems in a number of commercial applications. Such optical assemblies include optical waveguides, planar light guide circuits (PLCs), waveguides for distributed feedback lasers, and other like assemblies. High quality optical assemblies are particularly useful in, for example, telecommunications, medical diagnostics, pharmaceutical research, and chemical process monitoring. Additionally, ultra high-performance optical waveguides, such as waveguides associated with high-performance filters and precision micro optics, have the potential to fill a critical role in the continuing demand for increased bandwidth in telecommunications and in providing major improvements in medical diagnostics and pharmaceutical applications.
Numerous difficulties exist in the manufacturing of quality optical assemblies, because many of the individual components of optical assemblies are typically small and technically complex. For example, the relatively small size of each component makes differences between the components, or even differences within individual components, difficult to discern. For instance, such differences may include optical differences across the end face of an optical fiber. For quality optical assemblies, the discontinuities between the individual components need to be minimized.
For example, to achieve maximum effectiveness, the optical characteristics of an optical waveguide""s end face usually must be considered when connecting it to an optical component such as another optical waveguide. The end face of the waveguide may be intentionally angled. Because the end face is angled, it is not uniformly perpendicular to its axis or the axis of the optical component to which it is to be coupled. (As used throughout the specification, the terms couple, coupling, coupled, etc. are defined as any joining of two optical components that results in any optical connection between the two components, a face-to-face nonpermanent connection between the components, or a face-to-face permanent connection between the components.) The angle may be very slight, but it may be critical to have the end face precisely aligned with the other optical component. To identify the optical characteristics and alignment of the waveguide""s end face, optical testing is conventionally used. In optical testing, test equipment measures the characteristics of light propagating through the waveguide. The measurements are used to determine the optical differences across the end face of the waveguide and the alignment of the waveguide with respect to the optical component. The waveguide is then rotated to achieve the proper alignment with the optical component.
Conventional optical testing is time consuming when performed in a manufacturing environment. For example, the manufacturing process must be interrupted to perform the testing to identify the waveguide""s alignment. The waveguide is then rotated for alignment with the optical component. Then, the manufacturing process may be interrupted again to perform another optical test to check the new alignment. If needed, the waveguide may be rotated again, and further testing interruptions may be required. Additionally, after the two components are coupled together, another testing interruption is necessary for quality control of the assembled components. Accordingly, the manufacturing process is delayed each time the optical testing is performed to identify the characteristics of the components. Furthermore, optical testing performed in a manufacturing environment is not as accurate as optical testing performed in a testing environment. The inaccuracy of that testing can cause improper alignment between the components, which provides a lower quality assembly.
Accordingly, there is a need in the art for an improved system for automated production of quality optical assemblies. There is also a need in the art for a device, system, and method that easily and quickly identify optical characteristics and other information of optical assembly components, without using time-consuming testing during the manufacturing process.
The present invention can solve the problems of conventional systems and methods by eliminating the need for repeated testing of optical components while assembling optical components. The present invention can provide a quick determination of the optical characteristics and other information of the optical components. Accordingly, the optical components can then be automatically and precisely aligned before being mated to form an optical assembly. Furthermore, the present invention can also allow a quick determination of the optical characteristics, information, and alignment of the components even after the components are mated together.
According to one exemplary embodiment of the present invention, a fiber optic segment can comprise an end face having a peripheral end area, a peripheral edge area, and a machine readable identifier that is readable from at least one of the peripheral areas. The peripheral end area comprises an outer portion of the end face. The peripheral edge area comprises the exterior, cylindrical edge (side wall) of the fiber cladding. The machine-readable identifier can be on the end face peripheral end area, in the fiber segment but readable from the end face, on the peripheral edge area, or in the fiber segment but readable from the peripheral edge area. In one exemplary embodiment, the machine-readable identifier could be, a bar code on the end surface, which can be readable from both the end face peripheral area or the peripheral edge area. In another exemplary embodiment, the machine-readable identifier could be a series of Bragg gratings, which can be readable from both the end face peripheral area or the peripheral edge area.
According to another exemplary embodiment of the present invention, an optical waveguide identification system can comprise an optical waveguide and a machine-readable identifier disposed within the peripheral area of the waveguide""s end face. The machine-readable identifier can be etched into the end face and can provide information about the waveguide. Such information can comprise optical characteristics, orientation, manufacturing information, and dimensions and compositions of the materials of the waveguide. The waveguide can also have a plurality of machine-readable identifiers disposed within the peripheral area of its end face, where each can provide different information.
In another exemplary embodiment of the present invention, an optical waveguide identification system can comprise an optical waveguide, a machine-readable identifier disposed within the peripheral area of the waveguide""s end face, and a machine-readable identifier disposed within the waveguide""s exterior (side) cladding. The information of the exterior identifier is accessible even after the waveguide has been joined to another optical component. The two identifiers can have the same or different information. The waveguide can also have a plurality of identifiers on its end face and cladding, with information provided in identifiers disposed within the end face being provided in a corresponding identifier disposed within the exterior cladding.
In yet another exemplary embodiment of the present invention, a system for assembling optical components can comprise a reading device that reads information comprised in the above-described identifiers of an optical waveguide. A controller then adjusts the orientation of the waveguide for proper alignment with a corresponding optical component, based on the information read from the identifier. The waveguide and the optical component can then be joined in a precise alignment to provide a quality optical assembly.
In another exemplary embodiment of the present invention, an optical waveguide identification system can comprise an optical waveguide having a mask on its end face and a machine-readable identifier disposed on the peripheral area of an end face of the mask. The mask can be opaque to at least some wavelengths of light, which can eliminate unwanted optical noise. Additionally, an identifier can be disposed within an exterior surface of the mask. A filter can also be provided on the end face of the waveguide. The filter can block or redirect certain wavelengths of light propagating within the waveguide to eliminate or redirect light of certain wavelengths or to pass only light of certain wavelengths. The optical assembly can then be used as an optical component in the manufacturing system described above.
According to another embodiment of the present invention, a method for assembling optical components can comprise providing a machine-readable identifier on an optical waveguide. Information contained in the identifier can be read by a reading device, and then the waveguide can be aligned for precise connection to an optical component, based on the read information. If desired, the information contained in the identifier can be read again, and the alignment of the waveguide can be fine tuned based on that read information. The waveguide and the optical component can then be precisely coupled together. After coupling the components together, the information in the identifier on the waveguide can be read again and used for quality control to verify proper alignment of the waveguide and the optical component.
These and other aspects, objects, and features of the present invention will become apparent from the following detailed description of the preferred embodiments, read in conjunction with, and reference to, the accompanying drawings.